[bArray]

Just throttle your router settings for download/upload - have fun!

In all seriousness though, people designing websites should be given the shittiest connections possible and old computers (between 5 and 10 years old). Maybe then we'll end up with websites that haven't got more JS than content, broken CSS and images that push the page download over several megabytes.

[d2kx]

Chrome Dev Tools let you simulate shit internet connection (2G, slow 3G, fast 3G, etc.) and Google encourages to this for development for the reasons you've mentioned.

[bArray]

It's awesome it exists, but useless if nobody uses it. I think the Google homepage is the only Google product I'm aware of that loads fast, minimal CSS and still loads without JS. Even on a modern computer, some websites have become completely unacceptable to run in the background (i.e. Facebook).

Installing NoScript and blocking external CSS was the best decision I ever made. Now use <25% of the RAM and <10% of the CPU I used to for the same number of tabs (in Firefox) - with a better experience because the browser isn't constantly trying to die.

The UK Government site team is my go to for a good web design philosophy: https://www.gov.uk/guidance/government-design-principles (Hell, if they could run the actual Government like this we would be in a lot better shape!)